Understanding the relationship between urban blue infrastructure and land surface temperature.

Urban heat island (UHI) effect has serious negative impacts on urban ecosystems and human well-being. Mitigation of UHI using nature-based solutions is highly desirable. It was well known that urban green infrastructure (UGI), i.e., urban vegetation, can effectively mitigate UHI effect. However, the potential of urban blue infrastructure (UBI), i.e., urban surface water, on UHI mitigation is not well understood, although its potential to lower UHI effect via evaporation is similar to the biophysical mechanism of evapotranspiration through vegetation. In this paper, we study the relationship between UBI and land surface temperature (LST) in Wuhan city in central China, using a normalized difference water index (NDWI), maximum local cool island intensity and the maximum cooling distance as indicators for the cooling effects of UBI, respectively. We found a significant negative linear relationship between mean LST and NDWI after NDWI passes a critical threshold value. NDWI is an effective biophysical parameter to delineate the spatial distribution of UBI. The cooling effects of UBI are influenced both by its size and shape. Water surface temperature decreased logarithmically with increasing UBI size, critical threshold values of UBI size corresponding to maximum cooling efficiency do exists. Maximum cooling distance and maximum local cool island intensity are also affected by the shape and size of UBI, and exhibit seasonal and spatial variations. These results provide insights for urban landscape planning regarding how to use UBI as a nature-based solution to improve urban thermal environment.

Measures of safeguard and rehabilitation for landscape protection planning: a qualitative approach based on diversity indicators.

Maintaining existing levels of landscape diversity is becoming more and more important for planning considering the increasing pressures on agricultural ecosystems due to soil sealing, sprawl processes and intensive agriculture. Norms for land-use regulation and measures for landscape Safeguard and Rehabilitation have to take into consideration these threats in landscape planning. Evaluating the diversity of agricultural ecosystems is a fundamental step for proposing sound approaches to planning and managing both soil and landscape, as well as maintaining the related ecosystem services. The paper proposes a method aimed at the qualitative evaluation of spatial diversity of agricultural landscapes using a reduced set of ecological indicators based on land-use vector data. Indicators are calculated for defined landscape units characterized by landscape homogeneity. GIS geoprocessing and spatial analysis functions are employed. The study area is the Province of Enna in Sicily (Italy), which is characterized by cultivation mosaics in its southern region, cereal cultivation in the central region and prevailing natural environments in the northern region. Results from the indicator calculations are used to define measures to be included in a Landscape Protection Plan. Safeguard and Rehabilitation measures are introduced, which link indicator scores to planning protection aims. The results highlight the relevance of some agricultural mosaics in proximity to streams and seasonal fluvial environments, where some undamaged natural environments are still present. For these areas, specific landscape safeguard measures are proposed to preserve their diversity features together with their original agricultural functions. The work shows that even with a reduced number of indicators, a differentiated set of measures can be proposed for a Landscape Protection Plan.

Assessment of hazards and risks for landscape protection planning in Sicily.

Landscape protection planning is a complex task that requires an integrated assessment and involves heterogeneous issues. These issues include not only the management of a considerable amount of data to describe landscape features but also the choice of appropriate tools to evaluate the hazards and risks. The landscape assessment phase can provide fundamental information for the definition of a Landscape Protection Plan, in which the selection of norms for protection or rehabilitation is strictly related to hazards, values and risks that are found. This paper describes a landscape assessment methodology conducted by using GIS, concerning landscape hazards, values and risk. Four hazard categories are introduced and assessed concerning urban sprawl and erosion: landscape transformations by new planned developments, intensification of urban sprawl patterns, loss of agriculture land and erosion. Landscape value is evaluated by using different thematic layers overlaid with GIS geoprocessing. The risk of loss of landscape value is evaluated, with reference to the potential occurrence of the previously assessed hazards. The case study is the Province of Enna (Sicily), where landscape protection is a relevant issue because of the importance of cultural and natural heritage. Results show that high value landscape features have a low risk of loss of landscape value. For this reason, landscape protection policies assume a relevant role in landscapes with low-medium values and they should be addressed to control the urban sprawl processes that are beginning in the area.

Agro-ecological analysis for the EU water framework directive: an applied case study for the river contract of the Seveso basin (Italy).

The innovative approach to the protection and management of water resources at the basin scale introduced by the European Union water framework directive (WFD) requires new scientific tools. WFD implementation also requires the participation of many stakeholders (administrators, farmers and citizens) with the aim of improving the quality of river waters and basin ecosystems through cooperative planning. This approach encompasses different issues, such as agro-ecology, land use planning and water management. This paper presents the results of a methodology suggested for implementing the WFD in the case of the Seveso river contract in Italy, one of the recent WFD applications. The Seveso basin in the Lombardy region has been one of the most rapidly urbanizing areas in Italy over the last 50 years. First, land use changes in the last 50 years are assessed with the use of historical aerial photos. Then, elements of an ecological network along the river corridor are outlined, and different scenarios for enhancing existing ecological connections are assessed using indicators from graph theory. These scenarios were discussed in technical workshops with involved stakeholders of the river contract. The results show a damaged rural landscape, where urbanization processes have decimated the system of linear green features (hedges/rows). Progressive reconnections of some of the identified network nodes may significantly increase the connectivity and circuitry of the study area.

Agricultural and green infrastructures: the role of non-urbanised areas for eco-sustainable planning in a metropolitan region.

Non-Urbanised Areas (NUAs) are part of agricultural and green infrastructures that provide ecosystem services. Their role is fundamental for the minimization of urban pollution and adaptation to climate change. Like all natural ecosystems, NUAs are endangered by urban sprawl. The regulation of sprawl is a key issue for land-use planning. We propose a land use suitability strategy model to orient Land Uses of NUAs, based on integration of Land Cover Analysis (LCA) and Fragmentation Analysis (FA). With LCA the percentage of evapotranspiring surface is defined for each land use. Dimensions and densities of NUAs patches are assessed in FA. The model has been developed with Geographical Information Systems, using an extensive set of geodatabases, including orthophotos, vectorial cartographies and field surveys. The case of the municipality of Mascalucia in Catania metropolitan area (Italy), characterized by a considerable urban sprawl, is presented.